[HELP] Horizontal Interference / Flicker on my LCD Screens

[seanvon]

So, I recently bought two new Asus VS228H-P monitors (under warranty), and noticed a strange horizontal interference on both. It occurs when I am using a single screen or dual screen. It's only visible on most solid, mid-to-dark tones. I have a lot of difficulty with the gradient in the background for steams's site, for instance. It's a little difficult explaining this, as a screen shot obviously looks fine, taking a picture of my screen looks fine, and when taking a video it just isn't clear enough. So if you need more description, let me know.

TROUBLESHOOTING I'VE DONE SO FAR:
From reading similar problems other PC users had, I tried different power cords and power strips, but that didn't fix the interference. I tried a different monitor on my build, and the problem didn't occur (it was an old Apple monitor with ADC adapter to DVI). However, I also tried my new monitors hooked up to a different Apple computer (DVI to DVI), and the monitors worked fine. Finally, I hooked my monitors up to my new computer using VGA with a DVI adapter (VGA in on monitors), and the monitors looked good (at 1080, 60hz).

I also used a bootable Linux thumb and the problem didn't show itself...so it has to be something related to the Mac OSX, no?

I've contacted ASUS, and there are no drivers for my screen. I've gone through everything possible to make sure my graphics card (EVGA GTX 560 Ti) is fully recognized and operating correctly (followed the directions on this post http://tonymacx86.com/viewtopic.php?f=15&t=35148). QE/CI Open CL are all working. Ran a LuxMark test and got a score higher than average for my card.

Beyond reinstalling/reformatting the card, I have tried different power cords, DVI dual and single link, HDMI to DVI, moving and reinstalling my GPU onto a lower slot, and temporarily removing wireless card and other PCIe cards, in case they were causing some interference.

Lion doesn't seem to want me to change the refresh rate, although I don't think that would be the problem, as I usually work at 60hz and these are solid colors, not a moving image. The only thing I haven't tried is using Micro HDMI. However, I only have one Micro input, and two screens, so that wouldn't really be too helpful, anyway.

MY ASSUMPTION:
Since it works as a PC, and it works with a VGA (monitor) to DVI (GPU) adapter, I'm assuming that the Mac OS is getting some misinformation about my screen when hooked up through DVI. I've also noticed my text-smoothing doesn't work over DVI, so perhaps this has something to with my my OS not recognizing my screens as LCD screens?

So...is there anyway to force my computer to recognize my screens as LCD screens? Or do you think something else could be the problem?

Thanks so much for your input! I hope it's all clear.

Monitors: Asus VS228H-P (both monitors have the same problem)
GPU: EVGA 560ti
CPU: Intel Core i7 2600
MoBo: Gigabyte z68x-ud3h-b3
PSU: OCZ ModXStream Pro 700W
OSX: Lion 10.7.3

 

[seanvon]

Hmmm...I guess my choice is "or VGA." C'est la vie.

 

[bru]

hey i have the same problem..when gettin the video signal out of the miniDP of my 6870 i get interference lines that become more obvious when looking at youtube or any page with lots of flash. I tought it was the card and I rma'd it. new car was sent and same interference was there... i tried the card in another pc and everything was as it should be , no interference..


i think its the power supply man.. im going to RMA my entire build to the shop to let them find the problem that causes the interference and rma that component.. but i think its the powersupply..



i mustSAY : interference in my case only occurs when using miniDP ports. DVI and HDMI works well ... :///